Army patrols tense Ivorian city

The authorities want to prevent another march

The security forces are out in large numbers in the main Ivory Coast city of Abidjan, where police say 25 people were killed in clashes on Thursday.

Armed police and soldiers stopped and searched the few cars on the empty streets, while helicopters circled overhead, AP news agency reports.

Sporadic shooting has continued the day after security forces stopped a banned opposition march going ahead.

President Laurent Gbagbo's government called the protest an "armed revolt".

The opposition had called for the protests to continue on Friday and Saturday but most people have stayed at home after Thursday's violence.

"Our call remains the same, the mobilisation continues but if our militants cannot go out without being shot, then let Abidjan be a ghost town," said Cisse Bacongo, a member of the opposition RDR party.

'Unacceptable'

Lobby group Human Rights Watch has condemned the security forces' actions.

"Equating civilian demonstrators with enemy combatants is totally unacceptable," said Peter Takirambudde, executive director of Human Rights Watch's Africa Division.

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"The state security forces had a duty to minimize the violence and act with restraint, but they have clearly failed to respect this obligation."

The opposition said that up to 40 people had been killed.

Two policemen were shot and hacked to death.

Following the violence, the former rebels, known as the New Forces, and the opposition announced that they were pulling out of the power-sharing government.

Opposition politicians claimed the police were carrying out reprisal attacks on the homes and families of militant members - but there was no independent confirmation of this.

The National Police Director General Yapo Kouassi insisted he gave strict orders for the police to maintain law and order using "conventional means".

He said he told his men that "even if protestors spat in their faces, they must not open fire".

The BBC's Lara Pawson in Abidjan says Thursday's events will leave many wondering whether the country will return to war, 18 months after a failed coup left the Ivory Coast divided in two.

The UN Secretary General Kofi Annan was "deeply disturbed" by Thursday's violence and urged all Ivorians to avoid confrontation, a UN statement said.

Maximum alert

The government had mounted a massive security operation to prevent the march against President Laurent Gbagbo.

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The main opposition parties planned the protest, saying President Gbagbo had failed to implement reforms agreed in a peace deal last January.

Rebel spokesman Konate Sidiki told the BBC, "We cannot be part of a government where the army is in the service of a dictator.

"There will be military consequences. The New Forces are now on maximum full alert," he said.

Thursday's violence was the worst to hit Abidjan since September 2002, when a coup attempt triggered civil war.

Ivory Coast was once a symbol of stability and prosperity in a very unstable region but has been divided in two for more than a year.